Figure 5.

Postulated actions of miR-21 and gene expression of early T-cell activation. Hypothesized pathways of expression and down-regulation. miR-21 is known to down-regulate AP1 (28), and from presence of its seed sequence in 3′-UTR of target genes miR-21 is predicted to down-regulate 4 targets approximately 24 h after activation; BTG2, TAGAP, SPRY2, and FASLG as miR-21 expression increases. It is possible that miR-21 provides a mechanism of self-limited induction regulating T-cell activation.